Synthesis and anisotropic magnetic properties of LiCrTe 2 single crystals with a triangular-lattice antiferromagnetic structure

Abstract

Abstract We report on the synthesis of LiCrTe 2 single crystals and on their anisotropic magnetic properties. We have obtained these single crystals by employing a Te/Li-flux synthesis method. We find LiCrTe 2 to crystallize in a TlCdS 2 -type structure with cell parameters of a = 3.9512(5) Å and c = 6.6196(7) Å at T = 175 K. The content of lithium in these crystals was determined to be neary stoichiometric by means of neutron diffraction. We find a pronounced magnetic transition at T N a b = 144 K and T N c = 148 K, respectively. These transition temperatures are substantially higher than earlier reports on polycrystalline samples. We have performed neutron powder diffraction measurements that reveal that the long-range low-temperature magnetic structure of single crystalline LiCrTe 2 is an A-type antiferromagnetic structure. Our DFT calculations are in good agreement with these experimental observations. We find the system to be easy axis with moments oriented along the c-direction experimentally as well as in our calculations. Thereby, the magnetic Hamiltonian can be written as H = H H e i s e n b e r g + ∑ i K c ( S i z ) 2 with K c = − 0.34 K (where | S z | = 3 2 ). We find LiCrTe 2 to be highly anisotropic, with a pronounced metamagnetic transition for H ⊥ a b with a critical field of μ H M M (5 K) ≈ 2.5 T. Using detailed orientation-dependent magnetization measurements, we have determined the magnetic phase diagram of this material. Our findings suggest that LiCrTe 2 is a promising material for exploring the interplay between crystal structure and magnetism, and could have potential applications in spin-based 2D devices.